Main spring tester



Cet, 11, 1932. E. F. LONG MAIN SPRING TESTER Filed March 17. 1930INVENTOR Ward 172.' L on ATTORN EY Patented Oct. 11, 1932 i i EDWARDFRANKLIN LONG, or SPARTANBURQSOUTH GABOLINA eppncafion ined Meren 17,1930. serial No. 436,561.

My invention isf-a main spring tester'and has as one of its objects theprovision loffa device `whereby the motive power of a main spring of awatch or other horological` instrument maybe accurately determined.

v A fur'thor'objeot yof the invention is toy provide a hand instrumentof "this character which embodies a graduated scale and a movableyindicator to be operatively connected with one of' the gearsof awatch-or other horological instrument sothat the 'strength' or motivepower ofthe main Vspringwill be transmitted to the indicator to movethesame over thescale and thereby accurately measure themotive powerofthe main spring.

The invention also contemplates a spring torce measuring device whereinthe vindicating element will beautomatically latched in Cal 2o positionuntil manually released.

AWith the pre `3edingv and otherobjects advantages in mind,l theinvention consists in the novel combinationof elements5 constructionsandarrangements of parts and'opera-` tions to be hereinafter kmore fullydescribed, claimed and illustrated in the accompanyingdrawing;"wherein:y

Figure 1 is an elevation of the invention in y operative position totest the motive power ofa watch main spring;

Fig. 2 is an elevation of the instrument with the cover plate removed toshow the interior mechanism; i

. Fig. 3 is a sectional view of the invention; VVFig. 4 is a fragmentarydetail view or Athe latch embodied in the invention;

Fig. 5 is a'per'sp'ective view of the indicat-` ing hand; and

. u F ig. l6 is a perspective view of one of the elements of theinvention;

' Fig. 7 is a perspective view of another part of the invention. i fReferring to the invention in detail a cir- A .cular casing 5 having aremovable side wall "-1'" 6 which is securedin place removablefastenings 7, is provided.l The removable wall Y 6 is provided with aYcrescent-shaped slot 81 and held therein is a transparentfstriporwindow 9. Y

o. Held'b'etween the removable wall and the' Vabout the graduated`flange 11 and as shown operated position and cannot return to Zero sidewalls of theca'sing 5 is a-disk 10 whichfis formed an offset flange 11which is also crescentshaped and is disposed n parallelism'with- :thewindow 9. Graduations 12 arey provi-ded on the outer face Vot the flange11 and are visible through lthe window 9.

Arranged within the casingris a body 13 which is secured to the rearwallof the casing by a fastening 14. As disclosedin Fig. 3V the body 13 isformed with an upstanding arm 15 which is spaced from the rear wall ofthe casing. A cylindrical boss 16 is formed' on the outer face of (thearm 15 and is pro# vided with ya circumferential groove 17. Anindicating `hand .'18 is adapted for movement 6;

in Fig. 5 oneend of this indicatinghand is formed with a yole 19. Theyoke 19Mis received within the groove 17 and has suiiicient frictionallengagement therewith as to normally hold the indicatinghandlstationary.

Means are provided for takingod power from one of the pinions P of thewatchto measure the Vmotive power ofthe main 'spring M andywhichcomprises a bell'crank lever having one leg20 arranged withinthecasingo toone side ofthe body 13 and its other leg21` eztended fromthe casing at an angle `thereto las disclosed in Fig. 2. An' arcuateymounting 22 is provided for the bell crank lever and issecured in placeby removable fastenings 23. At a point intermediate the ends the'b'ellcrank lever is pivotally supported on a pivot 24' which extendstransversely through the mounting 22 and is engaged with -85 the rearwall of the casing. To permit pivotal movement of the bell crank leverthe mounting is provided with an elongatedre-A cess 25 while the casingis provided with a slot 26 in registration therewith. 90

4The inner end of the leg 2O 'of the bell crank levercarries alongitudinally curved rack 'bar 27 which extends in a directionlaterally of the leg 20 yand is movable between .J5

ythe arm 15 andrear wall of the casing. Ex-

tending transversely through the outer end of this arm 15 and'engaged,withv the rear wall of the casing is a shaft 28 'uponl which apinion 29 is rotatably 'mountedg` the latter lou i being engaged by thelongitudinally curved v29 and is located in the rack bar 27.

For the purpose of moving the indicating hand on its axis a laterallyprojecting pin 30 is carried by thefront facev or the pinion path ci'the indicating hand 18. a f

For the purposeofresisting theeiipansion of the main' spring M oftheWatch, a con- VY the` pinion l? and for this' purpose a bevelled.

vlug 34 lis 'formed on one tace oi" thisk free h l; Y. ,n slot 8. Asshown in Fig. 3 this pin projects In ord'erto automatically. latchtlieindiend of the leg'21.

` cating hand in actuated position the under face of theracl; bar 27 isformedwith ratchet teeth 35. A resilient arm 36 isA supported Ya'tfrigh'twangles to: the inner end. of theflegf; 2Qiof'the bell crankleveriromalug 37 carried'by the inner faceof lthe side Wallsfofthecasing. At its ree'end the resilient arm is formed ,With a pavvl 37which Yis ,resill iently held againstthe ratchetteeth 35. It(

will bel seen that upon movement of the leg 20- avvayy from the arm; 15Vtheuratchetteeth Y vWill successively engagethe pavvl 37a. `Thusihepinion se'wiii be posawny'heia against accidenttal vrotationY andconsequently the'- A"pinBO, Will beheld against the indicating n hand18and holdV it in adjusted position.;V It

Will therefore be manifest thatvtlieindicating handwill always give atrue reading. 1

' In order to disengage thepavvl 37a from. the ratchet vteeth a springpressed ,plunger 38 is slidably mounted in the rear Wall .ofthe casing"to one side ofY the resilient armi .36.

apoint'e'd head39 Which contacts With the 'resilient arm andits purposeis to move the latter laterally to disengage the paWl 8? from `theratchet teeth. As the plunger pressedinvvardly the pointed head willslidev off thel resilientarm Ato prevent undue strainV von the latter;InV other VYWords' the head will move the arm just enough to disengagethe -paivl from the'ratchet teeth. A linger engaging element 40 'is"carried by the outer fend. of; the spring pressed plunger and f 'iismovable into ia circularrecess 41 in the vouter ytace ofthe-rear Wallof' `the casing,

against the action of a spring 41a.V

-When it is desired to test the motive power ofthe horological,finstrnmentthe device is. `held inone handwith thelug 34 engaged withthe pinion .P The torce'or expansion ofthe springnM isutransmitted tothe bell crank lever and is'presisted by the actionof,

the contractlespring S1, `As thepinion is*` the graduated scale until.the contractile springA 31 overcomes the action otthe main spring end.The position ofthe indicating hand on the dial will then indicate themo-Y tive power of the `main spring.-

For the purpose of resetting the indicating vhand after each operationof the device a rotating finger engaging element 42 is mounted onza stud43 projecting laterally from the centery of the removablevvall 6. Thisrotatable member carries a laterally extending pin 44 Awhich Jassesthrough thefcrescent-shaped slot 45 W ich-is arranged concentric totheinto the path of the indicatingl hand sothat upon turningof themember 42in a counterclockwise direction the indicating hand Will beinoved to thezero position. To normally urge the rotatable member 42 to a positionWhere the pin 44 Will not engage the indicating hand 1 8 a. helicalspring 46 is arranged Within the finger engaging member andhas one end`anchored to the stud as at 47 and its Voppositeend anchoredto the Wall6 as at 48.

" l/Vhat is claimedis: Y. y v

1. In al device otthecharacter described, a

body havin la graduated scale thereon, a

lever 4pivuota ly supportedl on the body and Vhaving' one endprojectingtherefrom for en gagement with one of the gear vvheels of ahorolo ical instrument as rin 'connected With the lever to urge the samein a direction' opposite to the direction of rotation of the gear',aipiv'otally mounted indicating element movable over the scale, arackbar attached to one end of the lever and extending laterally y Ytherefrom,I a pinion.y suppo-rtedron the'V body Theinner end of theplunger is formed With and engaged by the rack bar, anda pin pro--jecting from the pinion and disposed in the A'lever pivotally",supported on the body and having` one fend, projecting therefrom for y.engagement With one of thergear Wheels vof a ho'rological instrument, aspringk connected with the lever to urgethe same in a direction oppositeto the direction of rotation of the gear, a pivotally mounted indicatingelement movable over the scale, a rack bar attached to one endet thelever and extendinglaterally therefrom, a. pinion supported'on the bodyand engaged by the rack bar, and a pin pro- Ajecting from. the pinionand disposed in the pathA of vthe indicating element'to move the latterover the scale incident to the movement ot the lever in one direction,anda manually releasable latch on the body for holding the lever inactuated position.

3. In adevice of the character described, a

casing, a lever pivotally supported intermediate its ends in the casingand having one end yprojecting therefrom and adapted to be engaged withone of the gears of a horological instrument, a spring'connected withthe lever and operable to resist movement of the latter in onedirection, said casing having a graduated scale thereon, an indicatinghand movable over the scale and means operable by the other end of thelever for moving said hand over saidl scale.

4.*In a device of the character described, a -casing, a lever pivotallysupported intermediate vits ends in the casing and having one endprojecting therefrom and adapted to be engaged with one of the gears ofa horological instrument, a spring connected With the lever and operableyto resist movement of the latter in one direction, said casing having agraduated scale thereon, an indicating hand movable over the scale,means operable by the lever for moving said hand, a resilient latch inthe casing and adapted to hold the lever in Vactuated position, and alaterally movable member supported at one side of the latch and`manually operable to` disengage the latter f from the lever.

5. In a device of the character described, a

. casing having a graduated scale thereon, a

v such bell crank lever pivotally supported therein and having one legprojecting therefrom and i 35 adapted to be engaged With one of thegears of a spring motor, a spring connected with the other leg andurging the lever in a direction opposite to the direction of rotationyof gear, ay rack bar carried by the last mentioned leg of the lever, apinion rotatably supported Within said casing to one side of the rackbar and engaged by the latter, an

indicating hand rotatably mounted in the casing, and a pin projectingfrom the pinion and disposed in the path of the indicator and operableto move the same over the scale when the bell crank lever is moved inone direction.

6. In a device of the character described, a casing' having a graduatedscale thereon, a bell crank lever pivotally supported therein and havingone leg projecting therefrom and adapted to be engaged with one of tleVgears of a spring motor, a spring connected with the other leg andurging the lever in a direction opposite to the direction of rotation ofsuch gear, a rack bar carried by the last mentioned leg of the lever, apinion rotatably supported Within said casing to one side of the rackbar and engaged by thevlatter, an indicating hand rotatably mounted inthe casing, a pin projecting from the pinion and disposed in the path ofthe indicator and operable to move the sameover the scale when the bellcrank lever is'moved in one direction, and a manually releasable latchin the casing and engageable With the rack bar to hold the same againstmovement When the bell crank lever has been moved in one direction.

7 In a device of the character described, a casing, a bell crank leverpivotally mounted therein and having one leg extending laterallytherefrom and adapted to be engaged with one of the gears of a springmotor, a sprin connected with the other leg of the bell crank lever toresist movement of the latter in one direction, a rack bar attached tosaid leg and extending laterally therefrom, a pinion supported'withinsaid casing to one side of the rack bar and engaged by the latter, a pinprojecting from the pinion, an indicating element pivotally supported onthe casing With its axis concentric with the aXis of the pinion andmoved yin one direction by the pin as the pinion is rotated in onedirection, said casing being provided With a scale over which theindicator moves, and a rotatable indicating hand resetting device on thecasing having a laterally projecting part Which is disposed in the pathof movement of the indicating move it to normal position.

EDWARD FRANKLIN LoNG.

